1. Field of the Invention
This invention relates to a novel device for releasably coupling a trailer to a towing vehicle, and particularly to an entirely mechanical device which is especially adapted for recreational use with a family automobile as the towing vehicle.
2. Description of the Prior Art
Much recreational equipment is transported by its users on trailers which are equipped with a drawbar having a hitching socket or yoke thereon. The towing vehicle is equipped with a hitching ball that is adapted to mate with the hitching socket on the trailer. Usually, the hitching ball is fixedly mounted on the towing vehicle, such as on the bumper of the vehicle. For coupling and uncoupling, the drawbar is physically raised to put the socket on or off the hitching ball.
Where the towing vehicle is a family automobile, it is desirable that the hitching ball and its support is low in initial cost, requires little maintenance, and is easily mounted and dismounted on the vehicle. It is also desirable that the coupling device assist in lifting the drawbar of the trailer.
When positioning a trailer in a limited space or in a precise location, at least for an occasional trailer user, it is easier to maneuver the trailer when it is coupled to the front of the towing vehicle rather than the rear. This front mounting is also advantageous at night when the vehicle headlights can illuminate the trailer, and also on a boat ramp where the rear wheels of the towing vehicle are furtherest from the water.
Many hitches and couplings have been suggested for coupling trailing carriages to farm tractors, highway trucks and automobiles, which devices are not particularly adapted for recreational use. Some devices include means for assisting the user in lifting the drawbar. For example, U.S. Pat. No. 4,148,499 to H. J. Johnson, describes a device comprising a support plate that is permanently mounted on the rear of the towing vehicle. The device includes a hitching ball mounted on a platform, a hydraulic cylinder and piston mounted between the support plate and the platform for raising and lowering the hitching ball, and a hydraulic system for operating the piston and cylinder. Such an arrangement is not adapted for a recreational user because it is too expensive to buy, install and to operate for recreational use; it is not easily mounted and dismounted on the towing vehicle; it is too bulky; and it is too complex to maintain economically.